How to change the default authorative domain in Exchange 2010

Hello,

Looking for some advice and help. I have an Exchange server which currently has 1 authorative domains, the default. myfirstdomain.com
I've just added a new authorative domain myseconddomain.com not set as the default. Mail records adjusted and now if I send email to a user at either domain it is delivered.
So far so good.
The reason for the second domain is a company name change which hasn't taken place yet.When it does I want to reverse the default, so senders are identified by the new company name and replied to using that domain but everyone will still receive mail sent to the old domain, at least for a while.
And so tot he question:
How do I change the default from one to the other and automatically generate the new addresses for each account?
If I look at the Accepted Domains tab under Hub Transport of the Management Console there appears to be no way to 'set default' although the current domain is marked as True and the new domain as False.
I think I need to edit the Email Address Policy on that corresponding Tab and add the new authorative domain to the Policy which will add the new address to all users, is there an option here to set the default?
Any help would be appreciated, I can't step throught he process as i am not ready to change the domain email addresses until the date of the company name change, but I want to be prepared.

For your default domain, you simply right-click the domain you want to make default, and click "Make Default".

To have users email sent out as your new company name, you edit the Default Email Address Policy, and right click the domain that you wish to make the default REPLY-TO address, and this will (assuming your AD doesn't override things) update all email addresses to have the default REPLY-TO address as the new domain.

Featured Post

The purpose of this paper is to provide you background on SQL Server. It’s your self-study guide for learning fundamentals. It includes both the history of SQL and its technical basics. Concepts and definitions will form the solid foundation of your future DBA expertise.